A medium supplying apparatus is an apparatus that separates one medium each time from a plurality of sheet-like media which are stacked and that supplies the separated medium and that is applied to an automatic document feeder mounted in an image forming apparatus such as a printer, an image reading apparatus such as a scanner, or the like. In such a medium supplying apparatus, it is necessary to separate and convey one medium at each time without causing double feed of media.
In such a medium supplying apparatus, in a case where a conveying error such as double feed occurs, a recovery operation for recovering the error, is performed by an operator. In the recovery operation, after opening a cover disposed at an error occurring spot and removing a medium that is the cause of the error, from the inside of the apparatus, the operator closes the cover and sets media again. Conventionally, in order to improve the efficiency of the recovery operation, a technology for performing control for automatically resolving a double feed in a case where the double feed occurs, is known (for example, Japanese Laid-open Patent Publication No. 2008-100828, Japanese Patent No. 4207796, Japanese Patent No. 4342249, and Japanese Patent No. 5559843).
Here, as an example of the control for automatically resolving a double feed in a case where the double feed occurs, for example, in Japanese Laid-open Patent Publication No. 2008-100828, a technology has been disclosed in which, when a double feed of sheet-like media is detected, in a state in which the retreat of an upper-side medium among a plurality of sheet-like media is prevented by using a reverse feed prevention member, a lower-side medium is returned according to reverse rotation of a retard roller.
However, in conventional technologies (Japanese Laid-open Patent Publication No. 2008-100828, Japanese Patent No. 4207796, Japanese Patent No. 4342249, and Japanese Patent No. 5559843, and the like), in a case where a double feed occurs, even when control for automatically resolving the double feed is performed, after a double feed state of a medium of which a double feed has been detected once is resolved, a situation in which a double feed is detected again for the same medium of which the double feed has been detected once may be considered to occur. The control according to the conventional technology is not a control process with such a situation being considered, and thus, there is room for further improvement in this point.